Prince Harry and Meghan Markle are up to date with Kate Middleton's condition, according to a royal expert.

The Duke and Duchess of Sussex allegedly only learned about the Princess of Wales' cancer diagnosis through TV, according to some reports. However, Tom Quinn, a royal biographer and author of "Kensington Palace: An Intimate Memoir from Queen Mary to Meghan Markle," said they were actually told in advance about it, but the specific details were kept from them, causing Prince Harry and Markle to allegedly feel "annoyed and frustrated" for not being prioritized in terms of being relayed important royal news.

"Harry was told about Kate's cancer the day before Kate's video was released, and they are definitely being kept up-to-date with Kate's condition -- apart from anything else, ignoring the couple completely would only lead to public attacks from Harry and Meghan and how they are being kept out of the loop and treated badly as usual," Quinn told the Mirror.

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The Royal Family Attend Church On Christmas Day
KING'S LYNN, ENGLAND - DECEMBER 25: (L-R) Prince William, Duke of Cambridge, Catherine, Duchess of Cambridge, Meghan, Duchess of Sussex and Prince Harry, Duke of Sussex leave after attending Christmas Day Church service at Church of St Mary Magdalene on the Sandringham estate on December 25, 2018 in King's Lynn, England.
(Photo : (Photo by Stephen Pond/Getty Images)

"They already feel annoyed and frustrated that they are no longer prioritized when it comes to this sort of thing -- it just reinforces their sense of victimhood, and that, rather than leaving the Royal family, they were pushed out."

Quinn, however, clarified that the Sussexes are "being told in advance, but only the major things." He explained that specific details are not disclosed to them because "they are no longer part of the inner circle," which was their decision.

"Let's not forget they brought this on themselves when they decided to leave Britain and cease to be working royals," Quinn added.

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Meghan Markle and Prince Harry
Prince Harry and Meghan Markle attend a reception for young people at the Palace of Holyroodhouse on February 13, 2018 in Edinburgh, Scotland.
(Photo : Andrew Milligan - WPA Pool/Getty Images)

Quinn also claimed that Prince Harry was "pressured" to keep his ties with the royal family amid his and Markle's ventures. He warned that Prince William's brother would be lost when things between him and Markle cool down, just like in the case of Edward VIII and Wallis Simpson.

"As Meghan and Harry become an older married couple and some of the fire goes out of their relationship, there's a real danger that Harry will feel lost -- just as Edward VIII felt lost when things had cooled with Mrs. Simpson," Quinn noted.

"That's the point at which Harry will really make huge efforts to build bridges with his brother and be allowed to be the part-time Royal (with Meghan) that he wants to be. But if palace officials have their way, it will never happen."

Prince Harry and Meghan Markle
Prince Harry, Duke of Sussex, and Meghan, Duchess of Sussex after attending the National Service of Thanksgiving at St Paul's Cathedral during the Queen's Platinum Jubilee celebrations on June 3, 2022 in London, England.
(Photo : Toby Melville - WPA Pool/Getty Images)